Description
Write what were condition within AMD CPUs may allow an admin-privileged attacker to modify the configuration of the CPU pipeline potentially resulting in the corruption of the stack pointer inside an SEV-SNP guest.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| AMD | AMD EPYC™ 9004 Series Processors | — | Genoa++_1.0.0.H |
| AMD | AMD EPYC™ 9005 Series Processors | — | TurinPI_1.0.0.6 |
| AMD | AMD EPYC™ 8004 Series Processors | — | Genoa++_1.0.0.H |
| AMD | AMD EPYC™ Embedded 7003 Series Processors | — | EmbMilanPI-SP3 v9 1.0.0.C |
| AMD | AMD EPYC™ Embedded 9005 Series Processors | — | EmbTurinPI-SP5_1.0.0.1 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | amd64-microcode | 3.20251202.1 | — |
| Debian 13 | amd64-microcode | No fix yet | — |
| Debian 12 | amd64-microcode | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.04 LTS | amd64-microcode | 3.20251202.1ubuntu1 | — |
| Ubuntu 25.10 | amd64-microcode | 3.20251202.1ubuntu0.25.10.1 | — |
| Ubuntu 24.04 LTS | amd64-microcode | 3.20251202.1ubuntu0.24.04.1 | — |
| Ubuntu 22.04 LTS | amd64-microcode | No fix yet | — |
| Ubuntu 20.04 LTS | amd64-microcode | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 14.04 LTS | amd64-microcode | No fix yet | — |
| Ubuntu Pro 18.04 LTS | amd64-microcode | No fix yet | — |
| Ubuntu Pro 16.04 LTS | amd64-microcode | No fix yet | — |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | spectre-meltdown-checker | 26.36.0602723-1.1 | openSUSE-SU-2026:11242-1 |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
GitHub 1 repository
-
fevar54/POC_CVE-2025-29943_Write-what-where-Condition ★ 0 · Jan 20, 2026
PoC de CVE-2025-29943 (StackWarp): corrupcion del stack en CPUs AMD Zen bajo SEV-SNP (write-what-where).
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Advisories 2
- openSUSE-SU-2026:11242-1 spectre-meltdown-checker-26.36.0602723-1.1 on GA media SUSE / openSUSE Security Updates · Jul 10, 2026
- WID-SEC-2026-0136 AMD EPYC-Prozessoren: Schwachstelle ermöglicht Manipulation von Daten BSI CERT-Bund (WID) · Feb 16, 2026